This week's top seeds are U.S. Open and reigning Rogers Cup champion Serena Williams, Wimbledon winner Petra Kvitova, Radwanska, French Open champ Maria Sharapova and Canadian favorite and Wimbledon runner-up Eugenie Bouchard. Last week's Stanford titlist Serena will open her Montreal stay against Stosur, who stunned the American in the 2011 U.S. Open final. Kvitova will face Dellacqua in the round of 32.